<template>
  <view>
   <!-- 使用自定义的搜索组件 -->
   <my-search @click="gotoStearch"></my-search>
  </view>
  <view class="scroll-view-container" >
    <!-- 左侧滑动区域 -->
    <scroll-view class="left-scroll-view" scroll-y :style="{ height: wh + 'px' }">
      <block v-for="(item, i) in cateList" :key="i">
         <view :class="['left-scroll-view-item', i === active ? 'active' : '']" @click="activeChanged(i)">{{item.cat_name}}</view>
       </block>
       
     
    </scroll-view>

    <!-- 右侧滑动区域 -->
    <scroll-view class="right-scroll-view" scroll-y :style="{ height: wh + 'px' }" :scroll-top="scrollTop">
      <view class="cate-lv2" v-for="(item2, i2) in cateLevel2" :key="i2">
        <!-- 二级分类的标题 -->
          <view class="cate-lv2-title">/ {{item2.cat_name}} /</view>
         <!-- 动态渲染三级分类的列表数据 -->
             <view class="cate-lv3-list">
               <!-- 三级分类 Item 项 -->
               <view class="cate-lv3-item" v-for="(item3, i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
                 <!-- 图片 -->
                 <image :src="item3.cat_icon"></image>
                 <!-- 文本 -->
                 <text>{{item3.cat_name}}</text>
               </view>
             </view>
        </view>
    </scroll-view>
  </view>
</template>

<script>
  export default {
   
    data() {
      return {
        //当前设备可用的高度
        wh: 0,
        cateList: [],
        active: 0,
        //二级分类的列表
         cateLevel2: [],
         scrollTop: 0
      };
    },
    onLoad() {
      const sysInfo = uni.getSystemInfoSync()
      //console.log(sysInfo)
      this.wh = sysInfo.windowHeight - 50
      
      this.getCateList()
    },
    methods: {
      async getCateList() {
        // 发起请求
        const { data: res } = await uni.$http.get('/api/public/v1/categories')
        // 判断是否获取失败
        if (res.meta.status !== 200) return uni.$showMsg()
       // console.log(res.message)
        // 转存数据
        this.cateList = res.message
        
        //为二级分类赋值
       this.cateLevel2 = res.message[0].children


      },
      activeChanged(i) {
        this.active= i
        
         // 为二级分类列表重新赋值
          this.cateLevel2 = this.cateList[i].children
          //console.log(this.cateList[i].children)
          
          this.scrollTop= this.scrollTop === 0 ? 1 : 0
      },
      //跳转到商品列表页面
      gotoGoodsList(item3) {
        uni.navigateTo({
          url: '/subpkg/goods_list/goods_list?cid=' + item3.cat_id
        })
      },
      gotoStearch() {
       uni.navigateTo({
          url: '/subpkg/search/search'
       })
      }
    }
  }
</script>

<style lang="scss">
.scroll-view-container {
  display: flex;
  .left-scroll-view {
    width: 120px;
    
    .left-scroll-view-item {
      background-color: #F7F7F7;
      line-height: 60px;
      text-align: center;
      font-size: 12px;
      
      &.active {
        background-color: #FFFFFF;
        position: relative;
        
        &::before {
          content: ' ';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #C00000;
          position: absolute;
          top: 50%;
          left: 0;
          transform: translateY(-50%);
        }
      }
    }
  }
  
  .cate-lv2-title {
    font-size: 12px;
    font-weight: bold;
    text-align: center;
    padding: 15px 0;
  }
  
  .cate-lv3-list {
    display: flex;
    flex-wrap: wrap;
    .cate-lv3-item {
      width: 33.33%;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      
      image {
        width: 60px;
        height: 60px;
      }
      text {
        font-size: 12px;
      }
    }
  }
}
</style>
